Our specific aim is to use and enrich existing patient self report and group level organizational data for patients receiving care in one of 58 managed care medical groups in California and the Pacific Northwest for the systematic analysis of the quality of medical are under varying features of managed care organizations. This collaborative effort between UCLA and the Pacific Business Group on Health (PBGH) will take place in an existing real world managed care laboratory whose infrastructure has been developed by PBGH. We will build upon Donabedian's model of the quality of care by conceptualizing and measuring multiple domains of structure including the organizational, financial, and clinical aspects of the structure of care; a clinically detailed evaluation of the processes of care; and condition specific and generic measures of health status and outcomes addressing patient's clinical and functional well-being. We are requesting funds to supplement completed or ongoing work regarding the relationships between multiple domains of: (1) baseline patient characteristics including health status; (2) medical group structure; (3) processes of care; (4) and outcomes of care. To conduct these analyses we propose to merge five categories of data (baseline patient self report survey, 24 month follow-up self report survey, baseline medical group survey, follow-up medical group survey, and medical record abstraction) from patients receiving care in 58 PBGH affiliated managed care medical groups. The proposed data collection and analyses demonstrate the commitment of PBGH to allow UCLA to use the real world managed care laboratory to conduct the proposed set of analyses which would not otherwise be conducted by PBGH.